Biocide activity of Annona coriacea seeds extract on Rhodnius neglectus (Hemiptera: Reduviidae)

The use of synthetic insecticides for insect control may lead to different kind of problems, such as vector resistance to insecticides. To avoid these problems, a new research area to study botanical products as possible disease vectors controls, has become a feasible alternative. The purpose of this research was to evaluate the biocide activity of the ethanol extract of seeds of Annona coriacea on Rhodnius neglectus (Chagas disease vector) nymphs and adults. For this, different concentrations extracts were evaluated: 25, 50, 100 and 200mg/ mL, and water in DMSO (20%) was used as control. The experimental design was completely randomized and we conducted the bioassay with nymphs and adults, with 10 nymphs and 10 adults (five males and five females) per treatment. Extract action was evaluated in both bioassays, in order to identify possible effects of mortality and life cycle interruption of nymphs and adults during a 28-day-period. The results obtained showed that the extract of A. coriacea was able to disrupt the development of nymphs and adults of R. neglectus, with a mortality rate of more than 90%, 36% and 100%, at the highest concentrations, respectively. There was also molting inhibition in nymphs, lower reproductive capacity in females, feeding deterrence and morphological changes in nymphs and adults. We concluded that the extract of A. coriacea has insecticide action on nymphs and adults of R. neglectus.

La enfermedad de Chagas se convirtió en un problema de salud debido a su importancia epidemiológica, es producida por el protista Trypanosoma cruzi, cuyos insectos vectores son del género Triatoma y Panstrongylus. El objetivo de este estudio fue evaluar la actividad biocida del extracto de Annona coriacea en las ninfas de Rhodnius neglectus y en sus adultos. Se evaluaron 14 concentraciones de 25, 50, 100 y 200mg/ml del extracto etanólico, así como el control, en este caso agua de DMSO (20%). Se utilizo un diseño completamente aleatorizado con tres repeticiones para el bioensayo con 10 ninfas y 10 adultos (cinco machos y cinco hembras) para cada tratamiento. La acción del extracto se observo durante 28 días en ambos bioensayos. Los resultados obtenidos mostraron que el extracto de A. coriacea fue capaz de interrumpir el desarrollo de las ninfas y adultos de R. neglectus, con una mortalidad de más del 90%, 36% y 100%, correspondiendo a las concentraciones más altas. También hubo inhibición de la muda de las ninfas, una menor capacidad reproductiva de las hembras, disuasión alimentaria y cambios morfológicos en las ninfas y adultos. Se concluye que el extracto de A. coriacea presentó acción insecticida en ninfas y adultos de R. neglectus.

Investigation of the toxic potential of crude ethanol extract of Annona coriacea (araticum) seeds in acute exposed mice

In this study, Annona coriacea Mart., Annonaceae, was examined for possible toxic effects on brain, liver and kidney of mice exposed to crude extract of the seeds (CESAN) of this plant. CESAN was administered by gavage for four days at doses of 12.5, 25, 50, and 100 mg/kg/day. Significant changes on liver were observed, which showed reduction in the number of hepatocytes per area and increase the apoptotic index in the exposed groups, and changes in the cytoplasm and nucleus of these cells and reduced consumption of water and feed in these animals. For the other studied areas, brain and kidneys showed no changes in the parameters used in this study. The results suggest hepatotoxic effects of CESAN, but without damage to brain and kidneys in this experiment, showing a toxic potential to this species, as to the Annonaceae family.

Chemical constituents of the volatile oil from leaves of Annona coriacea and in vitro antiprotozoal activity

The essential oil of the leaves from Annona coriacea Mart., Annonaceae, was extracted by hydrodistillation in a Clevenger apparatus and analyzed by GC/MS and GC/FID. The oil yield was 0.05 percent m/m. Sixty compounds were identified, in a complex mixture of sesquiterpenes (76.7 percent), monoterpenes (20.0 percent) and other constituents (3.3 percent). Bicyclogermacrene was its major compound (39.8 percent) followed by other sesquiterpenes. Most of the monoterpenes were in low concentration (<1 percent). Only β-pinene and pseudolimonene presented the highest level of 1.6 percent. The volatile oil presented anti-leishmanial and trypanocidal activity against promastigotes of four species of Leishmania and trypomastigotes of Trypanosoma cruzi, showing to be more active against Leishmania (L.) chagasi (IC50 39.93 µ g/mL) (95 percent CI 28.00-56.95 µ g/mL).